Flipkar — Not able to login

I have received recycled SIM card from Airtel
When I try to register on Flipkart, I get the message 'Account with this mobile number already exists please login'
But I can't login as I don't have password. A/c was created by previous owner of SIM Card
When I enter my mobile number and click on Forgot Password, Flipkart is asking for 2 OTP's. One sent on my mobile and one sent on email id. But email id belongs to the previous owner of SIM Card who has created the A/c

I contacted Flipkart. They asked me to send ID Proof from my new email Id
I sent it to them on [protected]@flipkart.com

4 days are over. They have still not resolved this issue. Every time I call them, they ask me to wait for 48 hours more

They are shameless, pathetic ###. They don't understand or sympathize with CUSTOMER's issues. They have worst CUSTOMER service in the world

Amazon is million times better than them